Rectifier for an electric generator

ABSTRACT

A rectifier for an electric generator, set up in a three-phase full-wave circuit, the metal case of which is in two parts each having on the joint surface an insulating base with built-in connecting tags for application of three-phase voltage to the semiconductor elements arranged inside each part of the case. The bolts holding together the cast parts simultaneously serve as d.c. output terminals for the rectifier and fasten the rectifier to a generator.

United States Patent Evgrafov et al.

[451 Aug. 15, 1972 [54] RECTIFIER FOR AN ELECTRIC GENERATOR Inventors:

Assignee:

Filed:

Appl. No.:

US. CL... Int. Cl......

Boris Ivanovich Evgrafov; Jury Alexandrovich Kupeev; Galina IosifovnaTurok, all of Moscow, U.S.S.R.

Nauchno-issledovatelsky i experimentalny institut Aoromobilnoggelecktrooborudovania i avtopribor00, Moscow, USSR.

July 9, 1971 ..32l/8, 310/68 D ..H02m 7/00 mi: of Search ..310/68 D;317/234 w; 321/8 [56] References Cited UNITED STATES PATENTS 3,160,77112/1964 Martin etal ..321/8 R X 3,275,921 9/1966 Fellendorf et a1..321/8 R 3,522,513 8/1970 Vogt ..321/8 R 3,612,927 10/1971 Anisimov..310/68 D Primary Examiner-William M. Shoop, Jr. Attorney-Eric H.Waters et a1.

1 RECTIFIER FOR AN ELECTRIC GENERATOR The present invention relates toelectric machines and, more specifically, to rectifiers for the electricgenerators used as supply sources for motor vehicles.

Known in the prior art is a rectifier for an automotive electricgenerator, set up in a three-phase full-wave circuit the semiconductorelements of which are com bined in three groups, each group having twoelements connected series aiding. Each group is built into a metal caseto which a phase voltage of the generator is applied. The like leads ofthe semiconductor elements are taken to current-collecting buses whichserve as d.c. terminals for the rectifier.

Among the disadvantages of this prior-art rectifier are that aninter-phase short may occur in service and also that it has an elaboratedesign.

Also known in the prior art is a rectifier for an automotive generator,likewise set up in a three-phase full-wave circuit whose semiconductorelements, which are encased diodes, are combined into two groups so thatthe elements of one group are fastened to one part of a split metal caseand connected to it with their P-regions while the elements of the othergroup are fastened to the other part of the case and connected to itwith its N-regions. This rectifier is built into the generator frame andcooled by the same air stream as the generator itself. Placed inside thegenerator frame, the rectifier is difficult of access for servicing. Itshould also be noted that this rectifier is complicated in design, sinceit uses encased diodes which require elaborate fixation of the caseparts to one another. Separate bolts are also required to fasten thisrectifier to the generator cover.

It is an object of the present invention to provide a rectifier for anelectric generator, which has sufficient heat abstraction for itsplacement outside the generator frame and is, at the same time, simplein design and re liable in operation.

With this object in view, the present invention resides in that in arectifier for an electric generator according to the invention each partof the case has at the joint surface an insulating base with built-inconnecting tags for application of three-phase voltage to rectifyingelements, and the parts of the case are held together by boltssimultaneously serving as d.c. output terminals for the rectifier and asmeans for fixation of the rectifier to the generator.

The invention will be more fully understood from the followingdescription of a preferred embodiment when read in connection with theaccompanying drawings wherein:

FIG. 1 shows a top view of a rectifier, according to the invention;

FIG. 2 shows section II-II of FIG. 1, according to the invention;

FIG. 3 shows section III-III of FIG. 1, according to the invention;

FIG. 4 shows section IV-IV of FIG. 1, according to the invention;

FIG. 5 shows section V-V of FIG. 1, according to the invention.

Referring to FIGS. 1 and 2, there is a rectifier which comprises a metalcase made up of two parts 1 and 2, each of which has three recesses 3holding encapsulated semiconductor elements (P-N junctions) 4 havingflexible leads 5.

The semiconductor elements 4 are electrically connected to the parts land 2 of the case by soldering so that one part of the case is incontact with the P-regions and the other part of the case is in contactwith the N- regions of the semiconductor elements 4. The parts 1 and 2of the case have each an insulating base 6 of the same construction.

In each insulating base 6 (FIG. 3) there are three connecting tags 7,anchored in the base as it is cast or by any other method; the tags 7are electrically connected to the flexible leads 5 by soldering orwelding.

To improve heat abstraction, the part 1 (FIG. 2) of the case has fins 9,and the part 2 of the case is attached directly to a cover 10 of thegenerator (not shown), exchanges heat and is in electric contact withit.

Referring to FIGS. 4 and 5, the parts I and 2 of the metal case and theinsulating bases 6 have holes 11 through which fastening bolts 12 and113 are passed. The bolt 12 serves at the same time as a positiveterminal and the bolt 13, as a negative terminal for the rectifier.

The bolt 12 (FIG. 4) is insulated from the generator cover 10 and thepart 2 of the metal case by an insulating grommet l4 and is in electriccontact with the part 1 of the metal case.

The bolt 13 (FIG. 5) is insulated from the part 1 of the metal case byan insulating grommet l5 and is in electric contact with the generatorcover 10 and the part 2 of the metal case. The part 1 of the metal caseand its insulating base 6 are brought in register with the part 2 of thecase so that the leads 5 of the semiconductor elements 4 correspondingto the full-wave circuit arrangement are in contact with one another viathe connecting tags 7.

The rectifier is fastened to the generator cover 10 by the same bolts 12and 13 passing through the holes 16 in the generator cover It).

The three-phase voltage of the generator is applied over the tags 7 tothe rectifying elements 4 combined into two groups set up in a full-waverectification circuit, with the result that a direct voltage appearsacross the parts 1 and 2 of the case and the bolts 12 and 13.

An advantage of the rectifier disclosed herein lies in that it has goodheat abstraction and may be installed outside the generator cover owingto which easy access is provided to it for servicing. Besides, therectifier disclosed herein is simple in design, as it consists of onlytwo parts which may be held together by only two bolts simultaneouslyserving as a means for the fixation of the rectifier to the generatorcover and as d.s. terminals.

What is claimed is:

l. A rectifier for an electric generator, set up in a three-phasefull-wave circuit, comprising: a split metal case made up of two parts;semiconductor elements arranged in one of the parts of said split caseand connected to it with their P-regions; other semiconductor elementsarranged in the other part of said split case and connected to it withtheir N-regions; insulating bases fastened each to the joint surface ofthe two parts of said case; connecting tags built into said insulatingbases and intended for application of three-phase voltage to all of thesaid semiconductor elements; two bolts holding together the two saidparts of the case and fastening the rectifier to the generator, whichalso serve as d.c. output terminals for the rectifier.

1. A rectifier for an electric generator, set up in a threephasefull-wave circuit, comprising: a split metal case made up of two parts;semiconductor elements arranged in one of the parts of said split caseand connected to it with their P-regions; other semiconductor elementsarranged in the other part of said split case and connected to it withtheir N-regions; insulating bases fastened each to the joint surface ofthe two parts of said case; connecting tags built into said insulatingbases and intended for application of three-phase voltage to all of thesaid semiconductor elements; two bolts holding together the two saidparts of the case and fastening the rectifier to the generator, whichalso serve as d.c. output terminals for the rectifier.